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Beta JD3 tug engines


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But do be aware...., its a big heavy engine and is rigidly mounted, so when running the engine (for battery charging etc) you will hear it and it will cause significant vibration in the boat. If you don't like this sort of thing then a modern rubber mounted engine would be better. I suspect it causes less vibration than a 2LW though!

 

..............Dave

 

 

This is my 2LW mounted on solid metal engine bed - no rubber mounts.

 

https://www.youtube.com/watch?v=CDZkvPWjqTI

 

Vibration?

Edited by mark99
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I've heard that you can halve the vibration from a hard-mounted engine by inserting some lead roofing sheet pieces between the engine and the bearers. I'd like to try it but not sure I'll get it right.

 

The benefits given by an engine in its own walk-through engine room are enormous. Drying room, heating assistance, tool storage on a rack on the lower wall next to the engine, to name but 4. Or is it 3.

 

You also end up with loads of space under the steering position, to store little-used but important stuff, for example a self pump-out rig with a couple of 25litre tubs to take it to the nearest bog.

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You also end up with loads of space under the steering position, to store little-used but important stuff, for example a self pump-out rig with a couple of 25litre tubs to take it to the nearest bog.

All I have is a weed hatch and a spare can of diesel

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This is my 2LW mounted on solid metal engine bed - no rubber mounts.

 

https://www.youtube.com/watch?v=CDZkvPWjqTI

 

Vibration?

 

Nice video (and engine room). I will try a coin on the JD3 tomorrow.

Not 100% convinced that the coin test is a representative one, especially on a most rigidly mounted engine.

Though did see a boat go past us last year with a big single cylinder engine and you could actually see the whole boat gong up and down.

Will the coin still stand up n the other direction (across the boat) and at the far end of the rocker cover????.

 

..............Dave

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A spare can of diesel? What for? Don't you have a diesel tank specially for storing diesel?

Actually thats quite a good idea. I'm always looking for some to soak me tea bags in!

I bought it after someone borrowed the diesel out of the tank and I ran out half way up Hatton in February one year

 

Nice video (and engine room). I will try a coin on the JD3 tomorrow.

Not 100% convinced that the coin test is a representative one, especially on a most rigidly mounted engine.

Though did see a boat go past us last year with a big single cylinder engine and you could actually see the whole boat gong up and down.

Will the coin still stand up n the other direction (across the boat) and at the far end of the rocker cover????.

 

..............Dave

It wouldnt stand on my BD3 but the 3 cylinder Gardner is far smother.

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Nice video (and engine room). I will try a coin on the JD3 tomorrow.

Not 100% convinced that the coin test is a representative one, especially on a most rigidly mounted engine.

Though did see a boat go past us last year with a big single cylinder engine and you could actually see the whole boat gong up and down.

Will the coin still stand up n the other direction (across the boat) and at the far end of the rocker cover????.

 

..............Dave

We use to do that on a Phillips spin dryer

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Hi All. I didn't log on to the forum yesterday so have missed all the banter! Sorry for the confusion about what I've got/am after. I have a 57ft narrowbeam DB with cruiser stern and want a 'normal' NB.

 

Love the coin video. Seems as though there's a lot of plusses about having an engine room.

 

Off to see the JD3 boat now. I'll see what my coin does on this boat's engine. The broker will think I've gone bonkers! Will report back later.

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The lettering will fall off the coin

 

Richard

 

The coin stands up easily anywhere on the rocker cover (600rpm fast idle) but does jiggle about a bit.

Whatever direction I place it in it always turns so as to be facing across the boat.

The lettering and queens head look ok'ish but maybe I should try to spend it in a pub to confirm that it still works.

 

I suspect there is more vibration in the saloon than in the engine room.....have put this on the list of interesting things to investigate.

 

..............Dave

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I don't know whether you guys recall me saying early on that I'm not fussed if the JD3 is a bit clattery? Well, I AM fussed. I might just be able to feel calm if there were 2 doors shut between me and it, but how can I say to any visitors staying over "Just have a lie in whilst I get underway in the morning."? Or what's the chances of me ever taking a photo of any wildlife whilst cruising?

 

AND I never got to do the coin check cause I just put my hand on the cylinder head in prep and decided my precious 2p coin I'd got ready was going to disappear amongst the engine ina matter of seconds . I also didn't want to look a mug.

 

As Dave (dmr) will have done, I used the coin instead in the pub and found the visit worthwhile cause I got chatting to an old stager who said I should consider Gardners. Providing I stick to the routine simple maintenance required he said the engine should last & last with very little problems (Now where did I read that earlier, Dave?)

 

So, I know I've discarded a couple of boats on my internet search because they had Gardners and I'm now just going to have to find them again.

 

PS Why do I bother going out for entertainment when all I need to do is log on to the Canalworld forum? Made me splutter eating my dinner, cuthound, with the Araldite reference.....

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I suspect there is more vibration in the saloon than in the engine room.....have put this on the list of interesting things to investigate.

 

..............Dave

This is an interesting point. If I were a clever engineer I could explain it properly, but to explain it improperly:

 

The energy in vibration relates to the frequency (let's discount that one), the amplitude, and the "tension" of the system. So the engine is closely coupled to the hull by bolts etc (unlike my nice smooth rubber mounted Beta 43) giving a lot of tension. Thus for a given amount of engine vibration energy, the amplitude is small. But further along the hull at the saloon, the tension of the coupling to the engine is much softer due to the flexibility of the hull's structure. Thus the vibration energy translates into a much larger amplitude, which you perceive as more vibration.

 

It reminds of being breasted up to a vintage-engined Hudson. Whilst having coffee aboard said boat, with the engine running, it was notable for very little vibration. But when said boat started up next morning to depart, our boat was shaking like a goodun due to the soft coupling to the vibration energy.

Edited by nicknorman
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You might get on better with standing waves, nodes and antinodes, Nick

 

Richard

But that is a resonance phenomena. So at different engine rpm, the vibration peaks and nulls would move around the hull. Whilst this is certainly A factor, I don't think it is the only one. Edited by nicknorman
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Our Gardner, as you can see from coin, does not vibrate too much but you can feel it in the engine room floor. In the saloon it's noisey (dog worrying noise). In cratch with saloon doors closed you can't hear much.

 

With a vintage engine you will feel it, smell it and hear it.

Edited by mark99
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Bet it's the most significant one. An engine pushes out a whole range of frequencies, setting of resonance in the hull won't be difficult

 

Richard

 

Not a whole range of frequencies really. There's mostly primary and secondary vibration (r and 2r), maybe rocking couple (depending on the engine configuration. The other vibration arising from eg gear meshing frequencies, camshafts, is normally (engine in good condition) of much lower energy.

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I don't know whether you guys recall me saying early on that I'm not fussed if the JD3 is a bit clattery? Well, I AM fussed. I might just be able to feel calm if there were 2 doors shut between me and it, but how can I say to any visitors staying over "Just have a lie in whilst I get underway in the morning."? Or what's the chances of me ever taking a photo of any wildlife whilst cruising?

 

AND I never got to do the coin check cause I just put my hand on the cylinder head in prep and decided my precious 2p coin I'd got ready was going to disappear amongst the engine ina matter of seconds . I also didn't want to look a mug.

 

As Dave (dmr) will have done, I used the coin instead in the pub and found the visit worthwhile cause I got chatting to an old stager who said I should consider Gardners. Providing I stick to the routine simple maintenance required he said the engine should last & last with very little problems (Now where did I read that earlier, Dave?)

 

So, I know I've discarded a couple of boats on my internet search because they had Gardners and I'm now just going to have to find them again.

 

PS Why do I bother going out for entertainment when all I need to do is log on to the Canalworld forum? Made me splutter eating my dinner, cuthound, with the Araldite reference.....

I have a BD3 not the JD but last trip I upset two fishermen (not wildlife) because they didn't hear me coming. But inside the boat its a different story. maybe you should look at http://www.nb-whisper.com/

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Well in my experience modern buzzy engines certainly create vibration but my K1 doesn't. Unless you count two thumps a second (a frequency of 2Hz) 'vibration'.

 

On the other hand the thump from each firing stroke certainly makes the galley cupboard doors and the cutlery in the drawer rattle a bit...

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Well in my experience modern buzzy engines certainly create vibration but my K1 doesn't. Unless you count two thumps a second (a frequency of 2Hz) 'vibration'.

 

On the other hand the thump from each firing stroke certainly makes the galley cupboard doors and the cutlery in the drawer rattle a bit...

Two thumps a second - vibration? Yes of course, at a lowish frequency. In line 4 cyl engines like our Beta are out of secondary balance so the vibration is at 2 x rotational speed and hence its perceived as "vibration" but not that much amplitude. It may even have a 2 x balancer shaft. Whereas your thumper is out of primary balance so low frequency yes, but big amplitude.

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